Direct Mechanical Ventricular Actuation (DMVA) is a non-blood contacting method for circulatory support which can be used in the failing heart, asystolic heart or fibrillating heart. The technology utilizes a contoured cup which attaches itself to both ventricles via a continuous vacuum. Once attached, positive and negative pneumatic forces move the diaphragm within the assist cup to "actuate" the ventricles into respective systolic and diastolic configurations. DMVA was originally designed only for short-term circulatory support in patients who suffered cardiac arrest refractory to standard resuscitative measures. Recent advances in support cup design and drive-line mechanics strongly suggest that the technology can be further developed to provide safe, effective and economical long-term circulatory support. DMVA has been extensively investigated in the Principal Investigator's laboratory over the past 4 years. Based on experimental results, Institutional Review Board approval was recently obtained for human use. DMVA support has been applied to 3 patients with refractory cardiogenic shock with 2 long-term survivors. The specific aims of the planned research are designed to perfect DMVA technology for both short-term and long-term, circulatory support. The planned studies to be carried out over the 4-year period of support include: 1) development of a DMVA Mock Circulation for in vitro cup testing for reliability and effectiveness of pumping under various pathologic states, 2) development of durable DMVA cups using modern industrial fabrication techniques with our Duke Biomedical Engineering and industrial consultants, 3) determine the effects of asynchronous versus synchronous DMVA support in an animal model, 4) determine the effects of DMVA on experimentally placed coronary artery bypass grafts, 5) apply the improved DMVA cups for total chronic circulatory support in animals, and 6) continue to apply DMVA support in select patients with refractory cardiogenic shock. Data from the planned studies will determine in detail the advantages and limitations of this form of biventricular assistance for total circulatory support. The eventual goal is to produce safe, reliable and effective DMVA support systems for widespread clinical use.